4x+8=20 -4x+4y=-10 Solve for X and Y

I'm at a bookstore with $\$35$ in my pocket and a $20\%$-off coupon. what is the cost of the most expensive book i can buy with my money and the coupon? (assume that there are books of every possible price in the bookstore. it's a large bookstore! )

Explain how the quotient of powers was used to simplify this expression.

In 2000 the average price of a football ticket was $48.28. during the next 4 years, the proce increased an average of 6% each year.a) write a model giving the average price (p), in dollars, of a ticket (t) in years after 2000.b) graph the model. estimate the year when the average ticket price was about $60